Stone tracer



ec. 4, 1953 R 5 MacKENz|E 2,577,535

STONE TRACER Filed Nov. 14, 1947 Patented Dec. 4, 1951 UNITED STATES `PATENT OF F ICE VSTONE TRACER Application November 14, 1947, Serial No. 785,852

2 GlaimS. (Cl. 125-440) This .invention `relates to'a method and apparatus for cutting stone, and more 'particularly the invention is concernedewith an .improved stone traci'ng :means for carrying .out scoring'or tracing Operations, in order-to'brea'k stone into desired shapes or sizes.

The task of scoring stone as commonly practiced requires a great deal of manual skill and is a slow and arduous operation. To this is added the danger of injur-y from stone particles or from the stone tracer fiying out of `the hand of the Worker. All of these factors .combine to impedc stone cutting Operations, `as well as increasing the cost of making granite products.

The invention is in general directed to 'improving-methods and apparatusfor stone cutting, and to reducing the dificulties noted 'to the greatest extent possible. Specifically it is an object of the invention to facilitate manual tracing Operations with improved tracing apparatus so that faster and more efiicient cutting may be carried out.

I have found that improved results may be obtained by surrounding a stone tracer with a holder member which is arranged closely adjacent to the sides of the tracer in such a position as to substantially limit displacement of the tracer at the time it is struck with a hammer. An important feature of the invention, therefore, is a method and means for both mechanically limiting displacement of a stone tracer when hammered and positioning the tracer between blows of the hammer. A more correct alinement of the tool may thus be maintained, with less effort and faster operation. Other objects and novel features will appear from the following description of the invention.

In the accompanying drawings illustrating a preferred embodiment of the invention:

Fig. 1 is a perspective view showing the holder and stone tracer assembly of the invention;

Fig. 2 is a plan view of the holder and tracer;

Fig. 3 is a cross section taken on the line 3-3 of Fig. 2

Fig. 4 is a cross section taken on the line 4-4 of Fig. 2;

Fig. 5 is a perspective view of a stone slab showing a line of scoring; and

Fig. 6 is a perspective view of a modification of holder member.

Considering the structure shown in the drawings in greater detail, I0 denotes a stone tracer which in general comprises a four-sided shank portion |2 and a relatively wider curvd tracing edge HI. This tool is made of steel and is com- 2 monly held in position by hand and struck with a c'onventional 'stone Hammer.

VIn accordance with the invention, I provide holder means for surrounding the tracer and loosel'yimaintaini-ng it in a substantially upright position, thus taking iaway a large part of the labor of holdingth'e'tr'acer by'hand. The holder may fbe made-'of metal, wood, plastic'o'r other vdesired material and includes a pair of parallel sides 16' and vlftiwhi'chfvhave fiattened portions 20 and 2 2 eXtending-'laterally outward to provide 'flat beairing surfaces. These `|.b'earing surfaces may, if desired, be further provided with cushioning means-22 vand 24, consisting of some lresilien't or yieldingly material Vsuch Vas layers of frubber or a rubber-likeisubstance.

The sides l6 and 18 are preferably `of a height less than the aheight of the stone tracer-when the latter member at'its lower extremity Vis supported in :the same plane'with ;the cushioning :means 122 and 24, as may be readily seen from an inspection of Figs. 3 and 4. The upper part of the tracer IO, therefore, extends well beyond the holder and is free to be gripped and hammered when desired. I may also desire to provide the tops of the sides IB and [8 with relatively wide fiange portions 30 and 32. The fiange portions are not essential to the holder but may provide a convenient supporting surface for the hand.

Numerals 34 and 36 refer to connecting partitions extending substantially at right angles between the sides IG and |8 in spaced-apart relation. These partitions may be formed by molding the holder or by using separate pieces as of metal which are welded to the sides in the manner shown.

The connecting partitions serve two purposes: they constitute spacing means for maintaining the sides IB and |8 spaced apart from one another a distance slightly greater than the thickness of the shank portion l2 of the tracing tool, measured in at least one dimension. At the same time, the two partitions are spaced apart from one another a distance also slightly greater than the thickness of the stone tracer, measured in a direction at right angles to the dimension just above referred to. By this arrangement, the shank portion |2 is surrounded on four sides with retaining walls or surfaces which are located sufiiciently close to respective adjacent shank portions to prevent rotation of the tracing tool. .Thus it will be seen that while some limited movement is provided for, there is a definite restriction on the amount of displacement of the tracing tool in a rotary direction and of course only limited movement laterally or longitudinally is possible, and the tracer is loosely maintained in a substantial upright position.

The partitions 34 and 36 extend from a point beginning approximately at the top of the sides IS and |8 downwardly to points somewhat above the relatively Wider Cutting edge |4 of the stone tracer as indicated in Fig. 4. It will be observed that the width of the cutting edge [4 substantially exceeds the width of the tool thrcughout the rest of its length. Therefore the tool can be inserted from the bottom of the holder upwardly into the position shown in Fig. 4 in which a slight clearance is provided for the tool to move vertically upward a short distance when hammered. It Will be evident, therefore, that the tracer is limited in its movement in all directions except vertically downward, thus preventing any substantial displacement of the cutting edge |4 as it is being hammered and preventing stone chips from fiying out at random.

In operation, the tracer is passed upwardly through the holder and the two elements are then located on a stone surface to be traced. The tool is then repeatedly hammered with the holder mechanically limiting displacement of the tool so that the operator may rapidly correct its position between each stroke. Concurrently with this operation, the operator moves the tracer and holder intoV successive cutting positions, with the tool in each position being located in a relatively central position within the holder, thus avoiding the need for carefully inspecting the placement of the cutting edge before each blow. In this way, a much faster and more accurate tracing line 38 may be formed on the stone surface, with a minimum of hazard and work.

An alternate form of the invention has been illustrated in Fig. 6 in which it will be observed that the two sides |6 and |8 are employed as before, but are joined together by end walls 49 and 42, extending between the side Walls at their extremities. This arrangement provides for a lateral supporting of the tracing tool on two sides, thus preventing any tendency for the tool to turn or rotate, without necessarily limiting upward or Vertical movement of the tracing tool when hammered.

I claim:

1. In combination a tool of the character described, presenting a, Cutting edge, a holder for maintaining the tool in a substantially upright position, said holder including a, pair of parallel vertical sides which extend beyond the Cutting edge to provide an elongated centering guideway, said sides being fianged laterally at their upper and lower edges, and a central shank support transversely mounted between the sides in a position to hold the Cutting edge of the tool in substantially centered parallel relation to the Vertical sides, said shank support terminating substantially above the bottom of the sides.

2. A claim corresponding to claim 1 in which the Vertical sides are provided with resilient laterally extending cushioning elements attached at the under surfaces thereof.

ROBERT S. MACKENZIE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 163,067 Hance May 11, 1875 1,658,418 Rinallo Feb. 7, 1928 2,0%,442 McNeil June 9, 1936V 2,090,47l Coffey Aug- 17, 1937 2,403,916 Ferguson July 16, 1946 

